Biologists discovered Buckeye butterflies with blue wings, leading to research on how structural colors are created by tuning the thickness of the lamina in butterfly wings. This understanding could help engineers develop photonic nanostructures for various applications, such as solar panels and cosmetics.

What unusual characteristic did the biologists observe in Buckeye butterflies?

• They were flying in unusual patterns.

• They had larger wings than usual.

• They were migrating to a new location.

• They had brilliant blue wings instead of brown.

Which organizations were involved in the research on Buckeye butterflies?

• The World Wildlife Fund and Greenpeace

• NASA and the National Science Foundation

• UC Berkeley and the Marine Biological Laboratory

• Harvard University and the Smithsonian Institution

Which part of the butterfly's wing is responsible for creating iridescent colors?

• The top layer of the wing scale

• The wing's central vein

• The lamina, the bottom layer of the wing scale

• The wing's outer edge

How many different species of Junonia did the researchers study to confirm their findings?

• Eleven

• Five

• Nine

• Seven

What potential applications could arise from understanding butterfly photonic nanostructures?

• Designing faster computer processors

• Creating more efficient solar panels

• Improving water filtration systems

• Developing new types of food packaging